The resource URL builders attached to app.route. Core attaches discussion, post and
user to the forum app at runtime; tag is added by the tags extension, and addForumRoutes()
backfills all of them on the admin app. None of these are present on the base app.route type,
so we expose a single narrowly-typed accessor instead of casting at every call site.
The resource URL builders attached to
app.route. Core attachesdiscussion,postanduserto the forum app at runtime;tagis added by the tags extension, and addForumRoutes() backfills all of them on the admin app. None of these are present on the baseapp.routetype, so we expose a single narrowly-typed accessor instead of casting at every call site.